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lacartus's profile

2 Messages

Thursday, April 18th, 2024 9:21 PM

UDM router has "no internet connection" when plugged into BGW320-500 port (Giga at bottom)

Newly installed BGW320-500 connects to the Internet, but I can't get my Ubiquiti Dream Machine (UDM) to reach the Internet when I plug it into the gigabit port (bottom port on BGW, there is a green light showing continuity).  Here's what I've tried:

1) just plugging in UDM and sending it...didn't work, but it was worth a try because that is all I had to do with our old CenturyLink fiber gateway/modem.

2) Set BGW to passthrough mode "DHCPS-fixed" selected the UDM from Passthrough Fixed MAC Address (it is the only wired connection), left DHCP lease at 10 minutes.  On Firewall Status: Packet Filter ON, IP Passthrough ON, NAT default server OFF, Firewall advanced OFF.  Some observations:

-- the BGW has a valid Internet IP address (not static, didn't pay for that)

-- the BGW says the UDM has IP and the gateway is on (web interface)

-- the UDM says it's IP address is (it is configured as  that's how I had it with Century Link)

-- if I plug a laptop into the BGW I can ping, but I can't ping or .2 any other address up to 10 (didn't try above that). 

-- if I plug a laptop into the UDM I can't ping 

My goal is to run my network on the UDM (with four switches) and only have the BGW wifi or ports for troubleshooting when my wife says the UDM network is down.  I assume Passthrough is the best for this, but I'll admit I don't understand what it is doing even after reading up on it -- it seems like the BGW has the Internet IP (WAN) and the UDM gets an internal 192.168.1.x IP where the BGW sends traffic it didn't originate to that IP for the UDM to handle.  Not sure if that's right. 

Anyway, any advice for getting to to work is much appreciated.   

Accepted Solution

ACE - Expert


35.6K Messages

1 month ago

First, you should not be keeping the same subnet (in this case for both routers.  Change one or the other.  Changing the Gateway is fine if you don't want to disturb your home networking.  

Two, if you actually got IP Passthrough to set up correctly, the UDM should try to renew its lease for (for now) and get told, no, you get the Public IP now.  That didn't happen, so that needs to happen.  Usually turning the UDM off for 5 minutes will take care of it (assuming you didn't disable the DHCP daemon on the other page and/or set its lifetime long).



187 Messages

1 month ago

I would factory reset both gateways and take it from there.

2 Messages

1 month ago

@JefferMC  Thank you!  Your two step advice was exactly what was needed, thank you!  My wife and work are up and running and the kids are not driving us crazy with all of their offline devices.  

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